Objective To investigate effect of dexmedetomidine on safety,validity and superiority in patients undergoing scoliosis surgery under propofol sufentanil anesthesia.Methods Forty patients undcrgoing elective posterior scoliosis surgery were randomly divided into groups D and C (n =10 each).Dexmedetomidine 0.8 μg/kg followed by 0.2 μg/(kg · h) and equal volume were infused at the 10 min before anesthesia induction in two groups,respectively.Hemodynamic parameters were observed at the 10 min before anesthesia induction (T1),3 min (T2) after anesthesia induction,1 min (T3) after intubation,at the beginning of wake-up test (T4),at the end of the test (T5),and 6 min (T6) after deepen anesthesia,respectively.Meanwhile the wake-up time,hemodynamic parameters,success rate of arousal,incidence agitation,and the bleeding volume during the test were also recorded.Results Successive rate of arousal awakening time between two groups had no statistical significance (P ＞ 0.05).Less incidence of agitation was found in group D compared to group C (P ＜ 0.05).The bleeding volume during the test was significantly less in group D (P ＜ 0.05).The hemodynamics was more smoothly during the operation in group D compared to group C (P ＜ 0.05).Conclusions Dexmedetomidine auxiliary propofol and sufentanil anesthesia can effectively implement intraoperative wake-up,reduce the amount of bleeding,and the incidence of agitation during the wake-up.The hemodynamics was more smoothly.